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A 440-V, 25 h.p (18.65 kW) motor has an armature resistance of 1.2 Ω and full-load...

A 440-V, 25 h.p (18.65 kW) motor has an armature resistance of 1.2 Ω and full-load efficiency of 85%. Calculate the number and value of resistance elements of a starter for the motor if maximum permissible current is 1.5 times the full-load current.

Answer: [1.92 Ω, 1.30 Ω, 0.86 Ω; 0.59 Ω]

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